Question

Please tell me how you solve these problems! I don't get it! :(

Answer 1

18 c

the answer is 7.5 square units

`((1 + 4) * 3) / 2 = (5 * 3) / 2 \\ = 15 / 2 = 7.5`


18 b

the answer is 10.5 square units

`((5 + 2) * 3) / 2 = (7 * 3) / 2 \\ = 21 / 2 = 10.5`

18 a

the answer is 12 square units

`((4 + 2) * 4) / 2 = (6 * 4) / 2 \\ = 24 / 2 = 12`




good luck

Answer 2

Lets get started :)

We know the area formula of a trapezium/trapezoid
Area =
`(1)/(2) (height)` (side 1 + side 2 )

In these examples, you need to note one thing very carefully, the graph is spaced with 2 units in the axes of x and y. It is not spaced with 1 unit
Which means: The axes begin as 2 , 4 , 6 ; - 2 , - 4 , - 6

18 ) c )
↓
Base 1 = 2 units
Base 2 = 4 + 4 = 8 units ( Only half the base length was shown, since it is the same below the x-axis, we multiply by 2 )
Height = 6 units

Apply the formula
Area =
`(1)/(2)` x 6 x ( 8 + 2 )
=
`(1)/(2)` x 6 x 10
= 30 units²

18 ) b )
↓
Base 1 = 2 + 2 = 4 units
Base 2 = 6 + 4 = 10 units
Height = 4 + 2 = 6 units

Area =
`(1)/(2)` x 6 x ( 10 + 4 )
=
`(1)/(2)` x 6 x 14
= 42 units²

18 ) a )
↓
Base 1 = 2 + 2 = 4 units
Base 2 = 4 + 4 = 8 units
Height = 4 + 4 = 8 units

Area =
`(1)/(2)` x 8 x ( 8 + 4 )
=
`(1)/(2)` x 8 x 12
= 48 units²